Tractor gearbox with rear-mounted main gear lever and rear-mounted auxiliary gear lever

Abstract

The utility model relates to the technical field of agriculture or forest machinery, in particular to a tractor gearbox with a rear-mounted main gear lever and a rear-mounted auxiliary gear lever. Comprising a gearbox shell, a shaft I and a shaft II, the shaft I and the shaft II are installed in the gearbox shell through bearings, the shaft II is parallel to the shaft I and is in transmission connection with the shaft I through a transmission gear, a shifting fork shaft is arranged above the shaft II, a shifting fork is fixedly installed on the shifting fork shaft, and the rear end of the gearbox shell is fixedly connected with a rear box body. A first variable-speed sliding rod and a second variable-speed sliding rod are installed in the rear box body, and the first variable-speed sliding rod and the second variable-speed sliding rod are both perpendicular to the shifting fork shaft. The gearbox is reasonable in structural layout and high in reliability, the main gear lever and the auxiliary gear lever can be properly arranged at the rear position, operation of a driver is facilitated, and misoperation is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of agricultural or forestry machinery, in particular to a tractor gearbox with a main and auxiliary gearshift levers being rear-mounted. Background Art

[0002] The tractor gearbox is one of the three major parts of a tractor. It is mainly composed of a speed change gearbox, an operating mechanism and a clutch. Its function is to change the speed and direction of the tractor so that the tractor can start, accelerate, decelerate, turn and reverse smoothly. It can also adapt the tractor to different working conditions and operating requirements. Among them, the single-axis gearbox generally adopts a mechanical manual speed change method to achieve the adjustment of different gears by manually switching gears. The single-axis gearbox has a simple structure and is easy to operate, but can only achieve limited gear shifting. In order to control the shift fork to shift gears, the shift lever of the existing single-axis gearbox is mostly set just above the shift gear, which is relatively forward and located in front of the driver's seat, which is inconvenient in actual operation. For example, the Chinese patent 2023215822910 discloses a "super-high-power tractor gearbox housing structure" with the authorization announcement number CN220015998U. The gearbox housing is provided with a gearshift slide rod installed inside the main gearshift slide rod hole 9 and the auxiliary gearshift slide rod hole 10. When the device is in use, the gearshift slide rod in the main gearshift slide rod hole 9 controls the shifting of the six main gears, while the gearshift slide rod in the auxiliary gearshift slide rod hole 10 controls the shifting of the four auxiliary gears. However, when the gearshift slide rod arranged just above the gearshift gear is used in conjunction with the gearshift lever, the position of the gearshift lever is still relatively forward, too close to the steering wheel, which makes it difficult to operate and hinders the operation of the steering wheel, which is prone to misoperation. Utility Model Content

[0003] The utility model aims to provide a tractor gearbox with a shifting slide rod located at the rear end of a gearbox shaft I and a rear-positioned main and auxiliary shifting levers. The main and auxiliary shifting levers are appropriately rear-positioned to facilitate the operation of the driver and avoid misoperation.

[0004] The technical solutions adopted by the utility model to solve the technical problems are as follows:

[0005] The utility model discloses a tractor gearbox with rear-mounted main and auxiliary gearshift levers, comprising a gearbox housing, an I shaft and a II shaft installed in the gearbox housing through bearings, wherein the II shaft is parallel to the I shaft and is connected to the I shaft through a transmission gear, a shift fork shaft is arranged above the II shaft, a shift fork is fixedly installed on the shift fork shaft, a rear box body is fixedly connected to the rear end of the gearbox housing, a first shift slide bar and a second shift slide bar are installed in the rear box body, and the first shift slide bar and the second shift slide bar are both perpendicular to the shift fork shaft.

[0006] By adopting this solution, the speed shifting slide rod is arranged at the rear end of the shift fork shaft, and the position of the speed shifting slide rod that controls the movement of the speed shifting slide rod will move backward accordingly, so that the positions of the main and auxiliary speed shifting levers are appropriately rearward, which is convenient for the driver to operate and avoids misoperation.

[0007] Preferably, a middle partition is provided between the gearbox housing and the rear case, and the front ends of the shafts I and II and the shift fork shaft are mounted on the front side plate of the gearbox housing, and the rear ends are mounted on the middle partition; the rear end of the shaft II extends through the middle partition into the rear case and is transmission-connected to the output transmission gear installed in the rear case; the rear end of the shift fork shaft extends through the middle partition into the rear case and is transmission-connected to the first speed shift slide rod or the second speed shift slide rod.

[0008] Through this solution, the speed-changing slide rod can be conveniently installed at the rear end of the shift fork shaft.

[0009] Preferably, the side wall plate of the rear box body protrudes outward relative to the side wall plate of the gearbox housing, and a side wall thickening area is provided at the junction of the side wall plate of the rear box body and the middle partition plate. The side wall thickening area is a protrusion extending inward from the side wall plate of the rear box body, and the first speed shift slide rod and the second speed shift slide rod are both installed on the side wall thickening area.

[0010] Through this solution, the thickness of the speed shift slide bar at the installation location is increased, which is conducive to the stable installation of the speed shift slide bar.

[0011] Preferably, the shift fork shaft includes a first shift fork shaft and a second shift fork shaft, both of which are axially movably mounted on the gearbox housing and have a U-shaped pull block fixedly mounted at the rear end thereof, the first speed shift slide rod is rotatably mounted on the rear case body, a first pull head is fixedly mounted on the first speed shift slide rod, and the first pull head is clamped in the pull block at the rear end of the first shift fork shaft; the second speed shift slide rod is rotatably and axially movably mounted on the rear case body, and a second shift head adapted to the pull block at the rear end of the second shift fork shaft is fixedly mounted on the second speed shift slide rod.

[0012] Through this solution, the speed change slide rod can control the movement of the shift fork shaft.

[0013] Due to the adoption of the above structure, the tractor gearbox with rear-mounted main and auxiliary shift levers of the utility model has a reasonable structural layout and high reliability, and the positions of the main and auxiliary shift levers can be appropriately rear-mounted to facilitate the driver's operation and avoid misoperation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a three-dimensional structural schematic diagram of an embodiment of the utility model.

[0015] Figure 2 It is a schematic diagram of the three-dimensional structure of the gearbox housing and the rear box. DETAILED DESCRIPTION

[0016] The present invention is further described in detail below in conjunction with the accompanying drawings. The same parts are represented by the same reference numerals. It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to directions in the accompanying drawings, and the words "bottom surface" and "top surface", "inner" and "outer" refer to directions away from the geometric center of a specific component.

[0017] like Figure 1 As shown, the tractor gearbox with rear-mounted main and auxiliary gear levers of the utility model comprises a gearbox housing 1, an I shaft 2 and a II shaft 3 installed in the gearbox housing 1 through bearings, the II shaft 3 is parallel to the I shaft 2 and is connected to the I shaft 2 through transmission gears. There are many specific numbers and combinations of transmission gears, and different transmission and speed ratios can be achieved through different transmission gear combinations, which will not be described in detail here.

[0018] A shift fork shaft 4 is arranged above the II shaft 3, on which a shift fork is fixedly mounted. The shift fork shaft 4 shifts the sliding gear in the transmission gear through the shift fork mounted thereon to achieve the meshing of different gear sets.

[0019] The rear end of the gearbox housing 1 is fixedly connected to a rear box body 5, which is an integrated structure formed by casting with the gearbox housing 1. A first speed shift slide bar 6 and a second speed shift slide bar 7 are installed in the rear box body 5, and the first speed shift slide bar 6 and the second speed shift slide bar 7 are both perpendicular to the fork shaft 4.

[0020] As a further improvement of the present invention, a middle partition 11 is arranged between the gearbox housing 1 and the rear box body 5, and the middle partition 11 is parallel to the front side plate of the gearbox housing 1, and mounting holes for installing the I axis 2, the II axis 3 and the fork shaft 4 are arranged at relative positions. The I axis 2, the II axis 3 and the fork shaft 4 are all installed on the front side plate of the gearbox housing 1 at the front end and installed on the middle partition 11 at the rear end; the rear end of the II axis 3 extends through the middle partition 11 into the rear box body 5 and is connected to the output transmission gear installed in the rear box body 5, and the output transmission gear transmits the power of the II axis 3 to the tractor running wheel through the left and right half shafts to drive the tractor running wheel to rotate; of course, the output transmission gear can also transmit power to the rear power output shaft of the tractor to drive the operation of agricultural machinery such as rotary tillers. The structure and connection method of the output transmission gear and the tractor running wheel and the rear power output shaft are all prior art and will not be described in detail here.

[0021] The rear end of the shift fork shaft 4 extends through the middle partition 11 into the rear box body 5 and is transmission-connected with the first speed-shifting slide bar 6 or the second speed-shifting slide bar 7. In this way, the movement of the shift fork shaft 4 can be manipulated by the rear first speed-shifting slide bar 6 or the second speed-shifting slide bar 7, thereby achieving gear shifting.

[0022] As a further improvement of the present invention, the side wall plate of the rear box body 5 protrudes outward relative to the side wall plate of the gearbox housing 1, and a side wall thickening area 51 is provided at the junction of the side wall plate of the rear box body 5 and the middle partition plate 11. The side wall thickening area 51 is a protrusion extending inward from the side wall plate of the rear box body 5, and a mounting hole for mounting the first speed-shifting slide bar 6 and the second speed-shifting slide bar 7 is provided on the side wall thickening area 51. The first speed-shifting slide bar 6 and the second speed-shifting slide bar 7 are both mounted on the side wall thickening area 51. In this way, the side wall thickening area 51 has a larger supporting contact surface with both ends of the speed-shifting slide bar, which can reduce the wear of the slide bar when it moves and improve the stability of the slide bar.

[0023] The shift fork shaft 4 includes a first shift fork shaft 41 and a second shift fork shaft 42. One first shift fork shaft 41 is used to switch between high and low gears. A plurality of second shift fork shafts 42 arranged in parallel with each other are used to switch between different gears. These second shift fork shafts 42 are arranged in a row along the axial direction of the second shift slide rod 7. The first shift fork shaft 41 and the second shift fork shaft 42 are both axially movably mounted on the gearbox housing 1 and a U-shaped pull block 43 is fixedly mounted at the rear end thereof. The cross-section of the pull block 43 is U-shaped and its opening direction faces the first shift slide rod 6 or the second shift slide rod 7. The first shifting slide bar 6 is rotatably mounted on the rear housing 5, and a first pull head 61 is fixedly mounted on the first shifting slide bar 6. The first pull head 61 is a cylindrical body or a spherical body fixedly mounted on the side wall of the first shifting slide bar 6 and the front end is adapted to the pull block 43. The first pull head 61 is clamped in the pull block 43 at the rear end of the first shift fork shaft 41. When in use, as long as the auxiliary shift lever installed at one end of the first shifting slide bar 6 controls the first shifting slide bar 6 to rotate a certain angle, the first shift fork shaft 41 can be pushed to move the axis of the first shift fork shaft 41 through the first pull head 61 to achieve the switching of high and low gears; in this embodiment, the left end of the first shifting slide bar 6 passes through the side wall of the rear housing 5 and is connected to the main shift lever. Of course, as another embodiment of the utility model, the auxiliary shift lever can also be installed at the right end of the first shifting slide bar 6.

[0024] The second speed-shifting slide bar 7 is rotatably and axially movable mounted on the rear housing 5, and a second shifting head adapted to the rear end shifting block of the second shift fork shaft 42 is fixedly mounted on the second speed-shifting slide bar 7. In this embodiment, the right end of the second speed-shifting slide bar 7 passes through the side wall of the rear housing 5 and is connected to the main speed-shifting lever, and the main speed-shifting lever can control the rotation of the second speed-shifting slide bar 7 as well as the axial movement of the second speed-shifting slide bar 7. When in use, the axial movement of the second speed-shifting slide bar 7 is first controlled by the main speed-shifting lever, and the second shifting head on the second speed-shifting slide bar 7 is inserted into the shifting block on one of the second shift fork shafts 42, and then the second speed-shifting slide bar 7 is controlled to rotate a certain angle, and the corresponding second shift fork shaft 42 is pushed to move axially by the second shifting head, and when the second shift fork shaft 42 moves axially, the shift fork pushes the sliding gear to move, so that the corresponding transmission gears are meshed with each other, and the gear position is switched.

[0025] Finally, it should be noted that the above is only a preferred embodiment of the utility model and is not intended to limit the protection scope of the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A tractor gearbox with a rear-mounted primary and secondary gearshift levers, comprising a gearbox housing (1), an I shaft (2) and a II shaft (3) mounted in the gearbox housing (1) via bearings, wherein the II shaft (3) is parallel to the I shaft (2) and is transmission-connected to the I shaft (2) via a transmission gear, a shift fork shaft (4) is disposed above the II shaft (3), and a shift fork is fixedly mounted on the shift fork shaft (4), and is characterized in that: The rear end of the gearbox housing (1) is fixedly connected to a rear box body (5), and a first speed-changing slide bar (6) and a second speed-changing slide bar (7) are installed in the rear box body (5), and the first speed-changing slide bar (6) and the second speed-changing slide bar (7) are both perpendicular to the shift fork shaft (4).

2. The tractor gearbox with rear-mounted primary and secondary gear levers according to claim 1, characterized in that: A middle partition (11) is arranged between the gearbox housing (1) and the rear housing (5); the I shaft (2), the II shaft (3) and the shift fork shaft (4) are all mounted at their front ends on the front side plate of the gearbox housing (1) and at their rear ends on the middle partition (11); the rear end of the II shaft (3) passes through the middle partition (11) to extend into the rear housing (5) and is transmission-connected to an output transmission gear mounted in the rear housing (5); the rear end of the shift fork shaft (4) passes through the middle partition (11) to extend into the rear housing (5) and is transmission-connected to a first speed-changing slide bar (6) or a second speed-changing slide bar (7).

3. The tractor gearbox with rear-mounted primary and secondary gear levers according to claim 2, characterized in that: The side wall plate of the rear box body (5) protrudes outward relative to the side wall plate of the gearbox housing (1), and a side wall thickening area (51) is provided at the junction of the side wall plate of the rear box body (5) and the middle partition plate (11). The side wall thickening area (51) is a protruding portion extending inward from the side wall plate of the rear box body (5), and the first speed shift slide bar (6) and the second speed shift slide bar (7) are both mounted on the side wall thickening area (51).

4. The tractor gearbox with rear-mounted primary and secondary gear levers according to claim 2 or 3, characterized in that: The shift fork shaft (4) comprises a first shift fork shaft (41) and a second shift fork shaft (42). The first shift fork shaft (41) and the second shift fork shaft (42) are both axially movably mounted on the gearbox housing (1) and have a U-shaped pull block (43) fixedly mounted at their rear ends. The first speed shift slide bar (6) is rotatably mounted on the rear housing (5). The first speed shift slide bar (6) is fixedly mounted with a first pull head (61), which is clamped in the pull block (43) at the rear end of the first shift fork shaft (41). The second speed shift slide bar (7) is rotatably and axially movably mounted on the rear housing (5). The second speed shift slide bar (7) is fixedly mounted with a second shift head adapted to the pull block at the rear end of the second shift fork shaft (42).

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